Gear generator



Dec. 29, -19422.' lw'. E. sYKEs k i 1 GEAR GENERATOR 8 Sheets-Sheet IL` Filed Dev. 28.19.58

Dag.' 29, 1942. w, E .SYKES 2,306,910

GEAR Gr-ENERATC-)R i Fgled Dc. 28, 1938 -e sheets-sheet 2 'laye ZSnventor (Ittomeg Dec. 29, 1942; w. E. sYKS 2,306,910

GEAR GENERATOR Filed Dec. 28, 1958 s sheets-sheet s Gttorneg Dec. 29, 1942. w. E. sYKEs 2,306,910

GEAR GENERATOR Filed Dec. 28, -193:3 s sheets-sheet :sy

Dec. 29, 1942.A

W. E. SYKES GEAR GENERATOR Fild Dec. 28, 1958 8 Sheets-Sheet 6 :inventor (Ittorneg Dec. 29, 1942; w. E. sYK'i-:s GEAR GENERATOR Filed Dec. 2s, 193s ZSnventor www@ dttorueg Dec. 29, 11942.

W. E. SYKES GEAR GENERATOR Filed Dec. 28, 1938 8 Sheets-Sheet 8 nventor v MII/'am E. 5L/Kes (Ittorneg `gear Shapers.

Patented Dec. 29, 1942 'UNETED STATES PATENT FFECE .GEAR GENERATOR William E.'Sykes, Manor Vtorks,v Staines, England Application December 28, 1938, Serial No. 248,090 In Great Britain October 29,1938

12 Claims.

Thisinvention relates to .improvementslin machines for cutting gears of they straightor helical type.

The invention is moreparticularly directed to machines which operate on themolding-generating principle of action, `more commonly termed -An object of the invention is vto providea machine of this .type which .will readily adapt itself to modern mass vproduction without the sacrifice of accuracyinthe cuttingoperations. The machine will therefore .be found to include novel structures, all devised witha view to mutual cooperation, simplicity of action, and `adaptability to high speed production.

ln its more specific aspect, `the machine includes a vertical arrangement ofthetool spindle, together with several novel .bearing organizations, to protect the driving connections'of thevcutter head against destructive stresses.

The work holdingporti-ons of the machine include a work saddle andan in-.feed mechanism therefor, which automatically-feeds the Work toward the cutterin intermittent steps,.and iinally withdraws the `work when the machining operation is completed. through a compactdriving mechanism which is .arranged to permitready access Vand adjustment,

so that the machinemay'beset up to produce .gears cfa `widerange-of sizes yand vtypes with a minimum ofeffort.

The various .novel features and vprinciples .of the invention andthe operatingadvantagesto be derived Vfrom .the use thereof .will-be moreapparent by a perusal ofthe following description and the accompanying drawings.

In the drawings: Fig. 1 is a sideelevation of the gear shaper;

Figs. 2 and 3 are front and rearelevations respectively;

Fig. 4 is a section on the line 4 4 of Fig. l; Fig. .5 is an enlarged section ontheline 5-5 of Fig. 1, showing thetop drive mechanism;

Figs. 6 and 7 areA sections onthe lines B-iand 'l-I respectively of Fig. 5;

Fig. 8 is a fragmentary section on' the line 8--8 w of Fig. 5, showing the clutch operating device;

Fig. 9 is an enlarged section on theline 9-9 of Fig. 2, showing the driving connections of vthe cutter head;

Fig. 10 is a 1l is a section on the line Il--l I of Fig. 9, showing the cam arrangement for obtaining the relief movementof thecutter head;

Fig. 12 is an: enlarged front view. of theinffeed control mechanism, with. the .cover broken away;

These units are operated section on the line lil-l0 of Fig. 9;

Fig.'13 is an enlarged section on` they line iS-I'S of Fig. 1, showing the driving connections'of vthe in-feed mechanism;

Fig. 14 is an enlarged section on the line lil-i4 of Fig. l, showing the work saddle details;

Fig. 15 is a perspective view of the work saddle cross-head and the complementary in-'feed cam block;

Fig. 16 is a section on the line IB-Ii of Fig. 4, showing details of the tailst-ockstructure.

The machine -operates on the so-called shapinggenerating principle of action, wherein a cutter C and a gear blank G (Fig. 1) revolve together'as if in perfect mesh, while the cutter additionally reciprocates axially in simulation of a shaper cutting stroke. In the useof the present machine, the chief duty of the operator is to remove the finished `gear or gears, and to affix new blanks 'in the Work saddle, since the operating cycle including the infeed ofthe blank, stopping of the machine, and Vrepositioning of the work saddle, may be ma-de entirely automatic. One operator may therefore attend a number of machines, which,V as will be observed in Fig. 2, are relatively narrow and straight sided, so that they may be arranged in a compact batt-ery. It will be noted that Various adjustable means 'are conveniently located on the front or operating side of the machine, while the :timing gears are all accessible through 'therear of the machine housing, as shown in Fig. 3.

The machine frame includes a base 3U,and,a superimposed pedestal 3l, whichis formed with a timing gear compartment 32 having a rear opening 33 covered by a vdoor 34 (Fig. l). The flat top 35 of the pedestal 3l receives the drive unit D of the machine, while the front wall 36 of the compartment 32 serves as a support for the cutter head unit H. The remaining major components of the machine, consisting ofthe work saddle unit S and the in-feed unit F, 'are disposed on the base 3B.

The'drzoe unit A main gear housing 38 (Figs.'2 and .5) Lis-secured to the righi-,hand side of the pedestal top 35, and it contains bearings 39, 4|,"42 for a drive shaft 40, which protrudes from the rear ofthe housing and receives a multiple pulley 43. A motor 44 mounted on the top '35 has a similar pulley 45 secured to its shaft, and it is connected to operate the pulley-43 by V belts 4t. Bevel gears G8, 49 are keyed to the shaft til, and they mesh withgears 5|, 52 which are carried by counter- .i shafts 53, 54 respectively. A third bevel gear' 55,

rotatably carried on the shaft 40 and positioned by a spacing sleeve S, meshes with a bevel gear 51 keyed to an angularly disposed countershaft 58 (Fig. 6) A clutch connection is provided to connect the gear 55 to the shaft 40 in a manner presently to be described.

The positively driven countershafts 53 and 54 are connected to mechanisms which respectively cause reciprocation of the cutter and the timed relief movement of the cutter head, while the motion of the last mentioned countershaft 53 controls the generating `or timed rotary movements of the cutter and gear blank, as well as the in-feed for the gear blank. It is important that the operator have an emergency control for rapidly stopping the progress of the automatic cutting cycle previously mentioned, and this is provided by the clutch connection between the gear 55 and the drive shaft 40 which permits instant cessati-on of the generating and .in-feed movements without the necessity of stopping the motor 44.

As will be seen in Figs. 5 and 8, the connection includes a clutch element 60 which is slidably keyed to the shaft 49, and which is formed with teeth 59. VThe gear 55 is formed with co-mplementary clutch teeth 6 An actuator yoke 62 engages a groove 63 in the element 60, and it is secured to a rod 64, one end of which is carried in a bearing 65, while the other end projects through the front of the housing 38. A small casing 67 (Fig. 8) is secured to this portion of the housing, and it contains vertically aligned bearings E8, 09 for a control shaft 19, to the upper end of which is secured an eccentric 1|. An eccentric strap 'i2 engages the eccentric 7|, and it is secured to the projecting end of the rod 64, and the strap additionally receives a spring 14 which engages the outer wall of the casing 61, and thus constantly thrusts the rod inward. The lower extremity of the shaft 'i9 is supplied with a lever 15, which, when turned to the right from the position of Fig. 2, moves the eccentric so that the rod 64 and accompanying clutch element 69 are moved inward to connect the element with the gear 55.

Referring now to the horizontal countershaft 53 (Fig. 5), it will be observed that it projects through a bearing 16 in the housing 33 and is connected to a companion shaft 53a by a coupling The latter shaft is mounted in bearings 18 in an adjacentl gear box 39, and it carries a gear 8| which meshes with a gear 82 secured to a crankshaftV 83. The crankshaft is carried in bearings 84, 89 in the gear box, and its projecting extremity is formed with a T-slot 81 for receiving a stud 88 which serves asan adjustable crank pin. A roller bearing structure 89 which is tted to the crank pin receives the big end 9| of a connecting rod 90, and the bearing structure and crank pin are held in place by a cover plate 92 and a clamping nut 93 on the pin 83. The connecting rod 99 will also be observed in Fig. 9. It will be apparent that by loosening the nut 93 and sliding the pin in the T-slot 81, the effective stroke of the connecting rod may be varied. As will presently be described, the connecting rod imparts reciprocatory movement to the cutter C, and thus the stroke adjustment permits the cutter to be adapted to the width of the gear blank or blanks about to be machined.

The cutter unit The lower end of the connecting rod 90 is bifurcated as indicated by the numeral 95 (Figs. 2 and 9), to receive the head 96 of a stud 91 which iii serves as a link connection to the guide or crosshead structure of the cutter unit (Figs. 9 and 10). The end 95 receives a wrist pin in the form of a bolt 98 having an eccentric 99 keyed to it. The eccentric is mounted in a bearing I0! in the stud 91. The eccentric is normally retained in a fixed position by the clamping force applied by nuts |02 on the bolt 98 (Fig. 2). It will be apparent that the eccentric may be clamped in any desired position, thus serving as an adjustable connection between the connecting rod and the crosshead.

The cross-head consists of a guide |00 and a spindle |04 which are rigidly secured together by a connection |05. The guide is bored to receive a multiple ball bearing structure |06, the inner races of which are rigidly clamped to the stem 9? of the stud 91 by lock nuts |08. The outer races of the bearing structure are retained between a shoulder 93 in the guide bore and a thrust plate i |0 which is secured to the upper end of the guide |00. The cross-head, although thus deiinitely coupled to the connecting rod 90, is additionally rotatably mounted on the stud 91 through the bearing structure. The spindle |04 of the crosshead is formed with a threaded hole |04a, which serves to receive a tool post C' to Which the cutter C is secured. Instead of the ball bearing structure |06, one or more thrust rings may be ernployed to connect the cross-head and stud 9'1.

The spindle |04 is supported by a vertical bearing ||2 forming part of a cutter head H3 which in turn is carried by a bracket I I4 secured to the front wall 36 of the pedestal 3| (Figs. 9 and 10). A cyclindricalV bushing ||5 is secured to the top of the head I3, and its inner bearing wall lia is concentrically spaced from the guide |99 to receive rotatably an interposed sleeve 1B. A worm wheel |20 is bored to t the outer wall |51) of the bushing H5, and it is also formed with an elongated hub H8 which extends upward for connection with the flange ||9 of the sleeve H0.

The worm Wheel |20 and sleeve I6, which may be considered a unitary structure in effect, are connected to the guide of the cross-head by keys |2|, which are carried by the sleeve ||6 and which engage in straight keyways |22 in the guide |00. As will be seen in Figs. 9 and 10, each key |21 is formed of two complementary, wedgeshaped sections |2 la, I2 Ib, one of which is rigidly' secured to the sleeve by screws The other section |2|b is axially movable by an adjusting screw I 'la to permit takeup for wear.

A casing |23, secured to the upper end of the cutter head I3, and a cover |24 which is secured to the casing, form a protective enclosure for the worm wheel |29. A worm casing |25 is secured to the left hand side of the casing |23 (Fig. 10) and it contains suitable bearings |24a, |2412, for a worm shaft |25, which projects through an opening |21 in the wall 36 and into the timing gear compartment 32. Avworm |30, carried by the shaft |29, drives the worm Wheel |29, and with it the attached sleeve I6.

As thus far described, it will be apparentV that as the cross-head is reciprocated by the crank mechanism, it also receives a rotary movement through the drive afforded by Worm |30, worm wheel |29, and the key connection between the guide |99 and the sleeve H6. Y

Cutter relief mechanism Referring again to the cutter bracket H4, it will be noted that the lower portion thereof (Figs. 9, 10, and 11) is formed with a chamber ||4a, in which are disposed attached side plates |3|, |33,

accaoio and a bottom plate |32, which, together with the wall |33 of the bracket, form a box bearing for receiving the rectilinear projection |35 of the cutter head H3. A wedge plate |39 is interposed between one plate |3| and the adjacent wall |31 to provide lateral adjusting means for the bearing structure. The lower surface of the cutter head contains a square way |39 which is angularly'disposed and is adapted to receive a cam member |99. The square ends lili, |92 of the cam member are received in laterally aligned bearing apertures |3|a |38a in the side plates |3| and |38.

A tappet |93 is secured to the end |92 of the cam member |99, and it is engaged by a cam |95 which is secured to a vertical shaft 59a. This shaft is carried in a suitable bearing in a box |99 secured to the side of the bracket ||9 and it extends upward for connection with the countershaft 59 by a coupling |41 (Fig. '1).

The timing of the drive mechanism is such that during each reciprocatory cycle of the described cross-head (i. e., the downward and the return movement), the cam |95 performs a complete revolution. During the initial part of the downward or active cutting stroke of the cross-head, the large cam member |49 is thrust to the right (Fig. ll) by springs |99, |99, until the cutter head is slid outward to its full extended position against a stop member which is secured to the plate |32. During this portion of the stroke, the rotating cam |95 presents its dwell portion Ia to the tappet |99, and is just clear of 'the tappet, and thus does not touch the cam member |99. stroke is reached, the lobe MEI) of the cam engages the tappet |93 and thrusts the carn member |99 to the left against the urge of the springs |49, |99. This causes the cutter head to recede slightly within the boX bearing of the bracket I to a relief position which is retained during the upward stroke of the cross-head.

Timing gea/r unit The previously mentioned clutch controlled countershait 59 (Figs. 3 and 6) extends through an aperture in the pedestal top and into the compartment 32 where it is coupled to an aligned shaft 53a. From this point the gearing is disposed and proportioned to transmit the proper relative speeds to the worm shaft |25, which causes rotation of the cross-head, and a work shaft |59 which drives the work and in-feed units S and F.

As shown diagrammatically in Figs. l and 3, the shaft 59o carries a bevel gear |53 which meshes with a gear |59 carried by a horizontal shaft |55. The latter shaft carries a second gear |55a which drives a reducing gear cluster |95, the final shaft |51 of which carries a gear |99. From here the drive is split, as two opposed gears |59 and |9| mesh with the gear |59, the former being attached to the worm shaft |29 and the latter being attached to a shaft 92, which drives a second gear cluster ibiza. The i'lnal gear |93 of' the second gear cluster meshes with a gear |94 which is secured to the work shaft |59.

The gear clusters |59, |5911 each include a group of gears which are removable and replaceable by other gears when it is desired to change the speed ratio between the worm and work shafts |25, |99 and/or between the main drive and both of these shafts. Inasmuch as clusters of this nature are well known in the mechanical arts, a detailed description thereof does not appear necessary, save However, as the end of the cutting to mention that they are disposed in a'position (Fig. 3) where they are conveniently accessible through the rear opening 33 in the timing gear compartment 32.

Work saddle unit A saddle |19 (Figs. l, 4, and 14), mounted for sliding movement on the machine base 39', is provided with gibs |99, |91 which are received in complementary ways |99 in the base. A cover |1| is secured to the saddle, and it and the saddle are supplied with aligned bushings |19a, |1|a, which receive a rotatable work spindle |99. The spindle is'formed with a central radial flange |12 which is retained between thrust surfaces |19b, |1|b of the saddle and cover respectively by interposed thrust washers |99, |19.

The spindle |89 is rotated by a worm |14 which meshes with a worm wheel formation |15 on the periphery of the spindle ange |12. The worm |14 is slidably splined to the previously mentioned work shaft |59, and it is carried in bearings |16 located in a worm casing |190, whichis secured to the side of the saddle |19. It will be observed that the bearings |19 position the worm against axial movement so that as the saddle is moved the worm is carried with it along the axially fixed shaft |59.

A table |11 is secured to the upper end of the spindle |89, and it serves as a mounting base for the gear blank or blanks G which may be carried on an arbor |19, which is secured in the bore |8911 of the spindle.

Where the relative proportions of the work demand it, a tailstock |99 is utilized to support the upper end of the work arbor |19. As shown in Figs. 1, 2, and 4, the tailstock includes a base |91 which is'secured to the cover `|1| of the saddle and which carries spaced vertical guide pins |92 having rack formations |92a thereon. A yoke |93 is formed with vertical bearings |93a, which slidably receive the pins |92, and horizontal bearings |93b vfor receiving a shaft |94 (Fig. 16). Gears |95 are lsecured to the shaft |94, and they are housed in pockets |94a in the yoke |93 and are disposed to mesh with the rack formations |92a on the pins and thus assure proper parallel movement of the yoke when it is adjusted to various heights. The bearings |9341 are split, as indicated by the numeral |99, and they are formed with drilled lugs |91 for receiving a bolt |91a which is utilizedto lock the yoke to the pins |92.

The yoke |93 is formed with a central projection |98 which contains a vertical gib portion |99 for receiving 'a dead center 299, whose body is formed` with a complementary gib portion 29|. A clamping slide strip 292 is disposed to engage a second gib portion 293 on the center 299, and itis ktapped toreceive a transverse screw 294 which projects through to the front of the yoke |93 where it receives a handle 299e. A plate 295, which is secured to the top of the center 299, is carried by a vertical screw 299 disposed in a suitable tapped hole in the projection |98. The screw 296 may be operated to raise or lower the plate 295 and accompanying center 299 to proper adjustment, whereupon the center 299 is rigidly clamped by turning the handle 299e which draws up the clamping strip 292.

11i-feed unit A rod 2|9 (Fig. 13) which is secured to the saddle |19 projects into the adjacent in-feed unit :F.and it is operated by the mechanism of the unit to move the saddle step by step towards the cutter, until the full depth of the gear tooth is attained, whereupon the rod and accompanying saddle are automatically withdrawn. As shown in Fig. 14, the rod isthreaded to enter a tapped hole 2|| in the saddle, and is locked thereto by a suitable lock nut.

The unit F includes a housing 226 having a horizontal slide portion 22| which receives a slide block 222 (Figs. 13 and 15). The rod 2li) projects through a hole 228 in the block and it is secured against axial displacement in the bearing structure by lock nuts 225. The block 222 is slotted as indicated by the numeral 226, and screws 221 are transversely positioned through the slotted portion to provide a clamp for securing the rod against rotation in the block bearings.

The rod 2|6 projects through the block 222 to the front of the machine, where it may be manually operated when it is desired to adjust the position of the saddle.

A transversely positioned control block 236 is disposed immediately beneath the forward end of the block 222 and it is guided in transverse rails 23| formed in the housing 226 of the in-feed unit. The upper surface of the control block 230 contains an angular cam groove 232 (Fig. 15) while the adjoining surface of the block 222 is formed with a complementary cam portion 233. The control block contains sockets 234 for receiving compression springs 235 which bear against the adjacent wall 236 of the housing 220 and thus urge the block to the left (Fig. 12). The control block is automatically locked against such spring-impelled movement by a mechanism consisting of rollers 231, 231e, which are disposed between the lower surface 23nd of the control block and the angular surface 2361 of a hardened insert 23B, which is affixed to the housing 220. The rollers are constantly urged into locking position by a spring-pressed plunger 239 which is likewise disposed beneath the control block. VA release finger 255 is located to the left of the rollers, and it is formed with a projection 240a which. as will presently be described, is engaged by other mechanism whereby the rollers are moved to the right to release the control block for the spring-impelled movement.

It will be apparent that when the control block 230 is moved to the right, the saddle slide block 222 and accompanying saddle |16 are moved toward the cutter C. At the same time the springs 235 are compressed in preparation for release of the block 236, and when such release occurs, the

control block is moved to the left and the saddle is accordingly moved away from the cutter.

The advance movement of the control block, that is, movement to the right thereof, which results in advance of the saddle toward the cutter, is operated by a control mechanism driven by the work shaft |55. This shaft extends into the housing 220 where it is carried in suitable bearings. An adjoining cam shaft 246, which is mounted in suitable bearings in the housing 220, is driven by the shaft |56 through gears 241, 248 secured to the shafts. The cam shaft 246 carries a cam 246a which operates a ratchet mechanism for driving a control mechanism 256 for advancing the control block.

The control mechanism includes a fixed shaft .l

25| which is secured in a boss structure 252 in the housing 226 and which rotatably carries a pawl arm 253. A lobe 254 on the extremity of the pawl arm is retained in contact with the cam -246a by a compression spring 255. A ratchet wheel 256 which is secured to a bearing sleeve 251 on the xed shaft 25| is engaged by a springpressed pawl 26| carried by a stud 258 on the ratchet arm 253. A spring-pressed ratchet 259, conveniently carried on an adjacent shaft 260, which will be described later, engages the ratchet wheel against retrogressive movement. As thus far described, it will be seen that as the cam shaft 246 is rotated, the pawl arm 253 is oscillated to cause intermittent rotation of the ratchet wheel 256 in a clockwise direction.

The bearing sleeve 251 also carries a control disc 262 which contains spaced radial slots 263 and an angular slot 264 for receiving studs 265, 266 on which cam rollers 2650i, 266a are rotatably mounted. A segmental cam insert 261 is secured to the disc, and it projects therefrom in the same plane as the rollers. The rollers, in counterclockwise order, are positioned at progressively greater radial distances from the axis of the disc 262, and, as the disc is rotated, they successively engage the left face 236e of the control block 236, and thereby move the block to the right. In Fig. 12, the first roller 266a has just engaged the block to start the feed cycle of the saddle, and it is followed by the second and third rollers, and finally the cam insert 261. The cam insert has a cam face 261a and a radial ydwell face 2615, the former face engaging and moving the block 230 a slight distance to give a final and finishing movement to the saddle, and the latter face retaining the block in such iinal position for a considerable period.

The cam insert 261 is a little wider than rollers 2650:, and the extra width makes contact with and thrusts the release nger 246 to the right, and, as it leaves the contact face 236C of the control block, it temporarily holds the nnger 246 in such depressed position to permit the block to be restored to its first position by the springs 235. As the block returns, it strikes a spring-pressed plunger 216 (dotted lines, Fig. 12) which is carried for sliding movement in a bearing 21| in the housing. As the plunger is moved to the left, a pin 21Da, carried thereby, engages and throws a switch arm 212 to open the circuit of the motor 44, thus stopping all movement of the machine elements.

To restart the machine, it is necessary to turn the control disc 262 manually a slight distance to permit release of the plunger 216 and the closing of the switch arm 212. This starting mechanism includes the previously mentioned shaft 26|] which is mounted in suitable bearings in the housing and which protrudes from the housing and is formed with a square end 2630i for receiving a suitable crank. The shaft 263 carries a pinion 214 which meshes with a gear 215 carried by the control sleeve 251.

General GDETCLZ'OIL The machine may be operated to produce simultaneously a plurality of gears of relatively narrow face dimensions, or in thev alternative to machine a single gear having a wide face.

cutter is thus provided, wherein the axial spacing of the elements is equalto the face width of the blanks G which are carried in parallelism on the adjoining work spindle. For proper operation of the machine, the stroke of the crosshead is adjusted so that it is slightly greater than the axial pitch of the cutter elements, with the result that an overlap of the strokes of adjacent elements is obtained. Inasmuch as the cutting elements are of identical formation, the gear blanks are formed with teeth which are uniform in character and which are devoid of too1 marks or any disi-lgurement.

Where it is desired to dispense with the short stroke method above outlined, the cutter may be of the usual single form. In this instance the usual practice may be followed in adjusting the stroke of the cutter to be slightly greater than the face width of the gear blank. It will be understood that the cutters may be of either the straight tooth or helical types. In the use of helical cutters, the cross-head guide |06 must be modied to contain helical keyways to obtain an additional helical twist during each stroke, as is well known in the art.

I claim:

l. In a gear shaper, a cutter head having a bearing, a cross-head carried for sliding movement in the bearing, a cutter secured to the cross-head, means for reciprocating the crosshead including a connecting rod, a multiple bearing structure disposed axially within the crosshead, said structure having outer races secured against axial movement to the cross-head, a

stud carried by the connecting rod and having A.

a stem extending through the bearing structure,

means securing the stem to the inner races of the bearing structure, rotatable means carried by the cross-head having a key connection with the cross-head, a bracket carrying the crosshead for guided relief movement transverse to the axis of the cross-head, and drive means for the cutter head operating in timed relation to the operation of the cross-head.

2. In a gear shaper, a cross-head having a cutter attached thereto, means for rotating the cross-head, means operating in timed relation to the rotating means for imparting reciprocatory movement to the cross-head including a connecting rod, a multiple ball bearing structure having outer races secured against axial movement in the cross-head, and a link member carried by the connecting rod and secured against axial movement to the inner races of the bearing structure.

,cutter attached thereto, means supporting the cross-head for guided axial movement, means for rotating the cross-head, means operating in timed relation to the rotating means for impart- :ing reciprocating movement to the cross-head, and a rotary connection between the reciprocating means and the cross-head including an axial bearing structure in the cross-head, a member retained in the bearing structure for relative rotary movement with respect to the cross-head, vand a pivotal connection between the member and said reciprocating means.

4. In a gear shaper, a cross-head having a cutter attached thereto, means supporting the cross-head for guided axial movement, means for rotating the cross-head, means operating in timed relation to the rotating means for imparting reciprocatory movement to the cross-head including a crank driven connecting rod, a rotary vconnection between the connecting rod and the cross-head including an axial bearing structure in the cross-head, a member retained in the bearing structure for relative rotary movement with respect to the cross-head, and a pivotal connection between the member and said reciprocating means, and means for moving the supporting means transversely with respect to the axis of the cross-head to provide a relief movementA 5. In a gear shaper,` a cutter head having a bearing, a cross-head carried for sliding movement in the bearing, a cutter secured to the cross-head, means for reciprocating Vthe crosshead, a rotary connection between said means and said cross-head, means for rotating the cross-head including a sleeve disposed about the cross-head and having a sliding key connection therewith, a cylindrical bushing surrounding the sleeve and secured to the cross-head, a rotatable member carried externally by said sleeve, means connecting the sleeve and member, and axial bearing means engaging the rotatable member and sleeve to prevent axial movement thereof.

6. In a gear shaper, a cutter head having a bearing, across-head carried for sliding movement in the bearing, a cutter secured to the cross-head, means for reciprocating said crosshead including a connecting rod, a multiple bearing structure disposed axially within the cross-head, said structure having outer races secured against axial movement to said cross-head, a stud carried by the connecting rod and having a stem extending through the bearing structure, means securing said stem to the inner races of the bearing structure, rotatable means carried by the cross-head, and a key connection between the rotary means and the cross-head.

'7. In a gear shaper, a cross-head having a cutter attached thereto, means supporting the cross-head for guided axial movement, means for rotating the cross-head in its supporting means, means operating in timed relation to the rotating means for imparting reciprocatory movement to the cross-head including a crankdriven connecting rod, a rotary connection between the cross-head and the connecting rod including an axial bearing structure in the crosshead, a member retained in the bearing structure for relative rotary movement with respect to the cross-head, and a pivotal connection bel tween the member and said reciprocating means,

and a cutter' relief mechanism comprising means for moving the supporting means and accompanying cross-head transversely with respect to the axis of the cross-head and to the axis of rotation of the connecting rod crank, whereby during relief movement said crank may pivot about its crank connection in the direction of relief movement of the cutter head.

8. In a gear shaper, a cross-head having a cutter attached thereto, means supporting the cross-head for guided axial movement, means for rotating the cross-head, means operating in timed relation to the rotating means for imparting reciprocating movement to the cross-head including a crank-driven connecting rod, a rotary connection between the connecting rod and cross-head including a connecting member for directly coupling the connecting rod with the cross-head, said member having a swivel connection with one of the connected elements and a pivotal connection with the remaining element and adjusting means incorporated in one of said connections for changing the effective length of the connecting member.

9. In a gear shaper, a cross-head having a cutter attached thereto, means supporting the cross-head for guided axial movement, means for rotating the cross-head, means operating in timed relation to the rotating means for imparting rotary movement to the cross-head including a crank and a connecting r'od driven by the crank,

nism mounted on the top of said pedestal and u including a driven crank, a connecting rod depending from the crank, a cutter head carried by the pedestal, a tool carrying cross-head mounted for guided vertical axial movement in the cutter head, a rotary connection between the end of the connecting rod and the cross-head including a connecting member for directly coupling the connecting rod with the cross-head, said member having a swivel connection with one of the connected elements and a pivotal connection with the remaining element, and means operating in timed relation to the crank for rotating said cross-head.

1l. In a gear Shaper, a machine base having an upstanding pedestal thereon containing a compartment, a drive mechanism mounted on top of said pedestal and including a driven crank, a connecting rod depending from the crank, a

cutter head carried on the exterior of the pedestal, a tool carrying cross-head mounted for guided vertical axial movement in the cutter head, a rotary connection between the end of the connecting rod and the cross-head including a connecting member for directly coupling the connecting rod with the cross-head, said member having a swivel connection with one of the connected elements and a pivotal connection with the remaining element, and means operating in timed relation to the crank for rotating said cross-head including a change speed transmission carried in said compartment and having a connection with said drive mechanism.

12. In a gear Shaper, a machine base having an upstanding pedestal thereon containing a compartment, a drive mechanism mounted on top of said pedestal and including a driven crank, a connecting rod depending from the crank, a cutter head carried on the exterior of the pedestal, a tool carrying cross-head mounted for guided vertical axial movement in the cutter head, a rotary connection between the end of the connecting rod and the cross-head including a connecting member for directly coupling the connecting rod with the cross-head, said member having a swivel connection With one of the connected elements and a pivotal connection with the remaining element, means operating in timed relation to the crank for rotating said cross-head including a change speed transmission carried in said compartment and having a connection with said drive mechanism, and a manually operable clutch connection between said drive mechanism and said transmission whereby the rotary movement of the cross-head may be controlled.

WILLIAM E. SYKES. 

